Most online social networks provide a mechanism for users to broadcast messages to their personalized network through actions like shares and tweets. Receiving positive feedback from the network such as likes, comments, and retweets in response to such actions can provide a strong incentive for the users to broadcast more often in the future. These interactions that influence a user to perform certain desirable future actions can be referred to as social incentives. For example, a user may want to broadcast an article to his or her network by sharing it. After the article shared by the user receives positive feedback such as a “like” from a friend, it can potentially encourage the user to continue sharing more regularly. Typically, for every user's visit to an online social network site, good messages need to be ranked and selected from a large set of candidate messages broadcasted in the user's personalized network by a recommender system.